How does your doctor make a diagnosis of FH?
Once your doctor has asked about your family history, taken blood tests and checked for physical signs of FH, they will use the Simon Broome criteria to see if you have it. You might be diagnosed as having definite FH or possible FH. Alternatively, they might use the Dutch Clinical.
The Simon Broome Criteria
A: Definite familial hypercholesterolaemia is defined as:
Total cholesterol greater than 6.7mmol/L or low density lipoprotein cholesterol (LDL-C) greater than 4.0mmol/L in a child aged younger than 16 years or total cholesterol greater than 7.5mmol/L or LDL-C greater than 4.9mmol/L in an adult (levels either pre-treatment or highest on treatment).
Plus:
Tendon xanthomas in patient or in 1st degree relative (parent, sibling, child) or in 2nd degree relative (grandparent, uncle, aunt)
Or:
DNA-based evidence of an LDL receptor mutation or familial defective apo B-100 or a PCSK9 mutation
B: Possible Familial Hypercholesterolaemia is defined as:
Total cholesterol greater than 6.7mmol/L or low density lipoprotein cholesterol (LDL-C) greater than 4.0mmol/L in a child aged younger than 16 years or total cholesterol greater than 7.5mmol/L or LDL-C greater than 4.9mmol/L in an adult (levels either pre-treatment or highest on treatment)
and at least one of the following:
Family history of myocardial infarction: younger than 50 years of age in a 2nd degree relative or younger than 60 in a 1st degree relative
Or:
Family history of raised cholesterol greater than 7.5mmol/L in adult 1st or 2nd degree relative or greater than 6.7mmol/L in child or sibling aged younger than 16 years
The Dutch Lipid Clinics Network Criteria
The Dutch Lipid Clinical Network criteria is used in the Netherlands to diagnose FH, but it’s sometimes used by doctors in Britain too. It works on a points system, where a set number of points are given to certain signs and symptoms, your cholesterol levels and illnesses in your family.
- a total point score of greater than 8 is considered "definite FH"
- a total point score of 6-8 is considered "probable FH"
- a total point score of 3-5 is considered "possible FH"
The Wales FH Service Criteria
There is also a Wales FH Service criteria which is a version of the Dutch criteria used in Wales.